Study Of Changes Of Architecture And Corneal Wavefront Aberrations Of Clear Corneal Incisions After Phacoemulsification

ChapterⅠAnalysisi of dynamic architectural changes of clear corneal incisions with diffrernt angles after phacoemulsificationObjectiveTo analyze dynamic architectural changes of 3.2mm clear corneal incisions with diffrernt angles using anterior segment optical coherence tomography(OCT).MethodsIt was a prospective case control study. Corneal incision quality was analyzed on 73 eyes of 63 patients using AS-OCT on the first preoperative day and the first postoperative day, week, and month. The angle of the incision was measured between the corneal surface tangent at the external wound opening and the line connecting the internal and external wound openings. Regarding the incision angle of 45°as a train spacing point, the patients were divided into two groups, set up control group and experiment group.Result1. The mean angle of the incisions of the control group (31.6±5.4)°was different from the experiment group (54.3±5.5)°2. There have statistical significance between-group differences in corneal thickness of incision, incision length, percentage of the incision length without coaptation in respect to the total length and endothelial gaping (P<0.01) at 1 day,1 week,1 month after surgery.3. However, there were no statistically significant between-group differences in descemet detachment (P>0.05)4.The percentage of epithelial gaping self-sealing is 100%.Conclusion1. AS-OCT is a useful and uncontacted tool in assessing architecture of clear corneal incisions of cataract surgery.2.The CCIs with large angle and short length will be disadvantageous to self-sealing and healing of the incision. 3. Desirable angle of CCI may help in the development of a consistent technique to create self-sealing incisions, cutting down the possibility of communication of anterior chamber and posterior chamber, and decreasing the risk for endophthalmitis.ChapterⅡStudy of changes of architecture of clear corneal incisions with different nuclear classification after phacoemulsificationObjectiveUsing anterior segment optical coherence tomography (AS-OCT) to study architectural changes of clear corneal incisions (CCIs) after phacoemulsification.MethodsIt was a prospective case series study. IOLs were implanted in 93 eyes of 82 patients after phacoemulsification through a clear-cornea, 3.2 mm incision without suture.Patients were observed on the first preoperative day and the first postoperative day and month, and the third postoperative month by AS-OCT. According to the Emery-Little nucleal classification system, the patients were divided into three groups, GradeⅡnucleus (31eyes) group, GradeⅢnucleus (31 eyes) group and GradeⅣnucleus (31eyes) group.Result1. There were statistical significant differences among changes of corneal thickness in different areas (center, superior and inferior of 3mm far from pupil center, incision area) befoe and after phacoemulsification F=306.23,288.34,52.17, 957.28,P=0.00)2. Among three groups, the corneal thickness of center, superior of 3mm far from pupil center and incision area had statistical differences (F=3.59,4.43,39.67, P =0.02,0.01,0.00)3. The interaction between time and nucleal classification (F=59.27,11.62,9.05, 25.65, P=0.00) was significant. Incidence rates of epithelial bubble, endothelial bubble, and endothelial gaping were maxlmum on the first preoperative day there were statistical differences among the three group (χ2=8.78,8.07,11.82, P=0.00, 0.02,0.00)4. On the first postoperative day month, the differences between endothelial bubble and endothelial gaping were significant (χ2=10.68, 15.29, P=0.01, 0.02, 0.00) After three postoperative month, all of them were regression.Conclusion1.Increasing corneal thickness of different areas were different after phacoemulsification.It manifested significantly on the first preoperative day. After three months of the surgery, all the cornea occurred reversible changes except the area of incision.2. Corneal thickness of different areas had different changes along with the time going.The edema of central cornea regressed fastest, the superior area of 3mm far from pupil center was second, the inferior area of 3mm far from pupil center was slowest.However, all of them regress thoroughly on the third preoperative month.3.We detected one case of gradeⅣnucleus with disperfective healing incision in the research, all the other cases had perfective healing. Epithelial bubble, endothelial bubble, endothelial gaping and descemet detachment in the patients with gradeⅢandⅣnucleus needed a longer healing time than in the patients with gradeⅡnucleusChapterⅢAnalysis of changes of architecture and corneal wavefront of clear corneal incisions of cataract with different locationObjectiveTo study architectural changes and corneal wavefront of clear corneal incisions (CCIs) induced by phacoemulsification with different location.MethodsCorneal incisions with different location were analyzed on 91 right eyes of 91 patients using anterior segment optical coherence tomography (AS-OCT) on the first preoperative day and the first postoperative day and month, and the third postoperative month. At 1month and 3month best corrected visual acuity (BCVA) and corneal wavefront aberration were examinded. Regarding the different locations as a train spacing point, the patients were divided into two groups, set up temporal incision (46eyes) group and superior incision (45eyes) group.Result 1. There was statistical significance between two groups, differences in corneal increasing thickness of incisions and incision length (P<0.05)2. There were statistically significant between-group differences in endothelial gaping (P<0.05)3. At 1 day after surgery, there were statistically significant between-group differences in descemet detachment and endothelial bubble (P<0.05)4. There were statistically significant between-group differences in uncorrected visual acuity (UCVA), BCVA, astigmatism, coma and trefoil (P<0.05).Conclusion1. In the near future of postoperation, temporal CCIs had smaller edema than superior CCIs, temporal CCIs are good for forming self-sealing incisions and will decrease the risk for endophthalmitis.2. In the far future of afteroperation, temporal CCIs lead to smaller surgically induced astigmatism and corneal wavefront than superior CCIs, the patients have perfect visual quality. Temporal CCIs are ideal phacoemulsification incisions.